Why is it called a 40 "breeder"?

[SoloChromis]

Simple question - Why does everyone refer to a 36"x12" 40g tank as a "40 breeder"?

 

[GhostCon1]

It's mainly used for breeding fish.

 

[joshky]

It's mainly used for breeding fish.

That or it was originally designed for fish breeders, I don't know if I would say it's more commonly used by breeders these days. I think both the planted and reefing community both really love this tank and possibly outnumber breeders using these dimensions anymore. But what do I know, just a guess.

 

[ca1ore]

It's an old term from the days when most tanks were taller than they were wide. The 36x18 footprint tanks were called 'breeders' because the greater width, and corresponding surface area, made them ideal for breeding fish.